1. Field of the Invention
This invention relates to trolling brakes for boats. In one of its aspects, the invention relates to a trolling brake mounted to the back of the boat to control the speed of the boat when the boat motor is running at idle speed.
2. State of the Prior Art
In trolling for fish, it is necessary to run the boat at relatively slow speed so that the lures are moving at a relatively slow speed through the water. It is very difficult to adjust the speed of the boat to a slow speed because the motor will stall if the speed is too slow. Frequently, the idle speed of the boat is too fast for trolling. It has thus been recognized that a brake is desirable in order to attain desirable trolling speed.
Brakes for stopping vessels are known. In the U.S. Pat. No. to Wendler, 655,140, there is disclosed a drag brake for stopping a large vessel wherein a scooped drag plate is supported on a pair of links which are pivotably mounted to the side of the stern of the vessel. The drag plate is raised and lowered by a windlass which winds a rope or cable secured to a drag plate. Although this drag plate may have been useful in stopping larger vessels, it would not be suitable for controlling speeds in a fishing craft. The shape of the brake is designed for maximizing braking power, not for providing a controlled flow of water at slow speeds. Moreover, the drag of the Wendler brake would not be uniform during the turning of the marine vessel, since the brake is structured only to impart a maximum braking force on forward movement and not turning movement. Also, the shape of the brake could encumber steering of the vessel. Further, the structure would likely result in tangling of trolling lines with the propeller system. Finally, the brake is stored on the aft deck of the vessel, and such an arrangement would be completely unsatisfactory in a trolling operation where people sit on the aft deck of the vessel.
Various systems have been devised to control the trolling speed of the boat. A common method is to drag a sea anchor behind the boat. This system is crude and quite unsatisfactory. The sea anchor is not easily controllable and can result in lurching of the boat.
A trolling plate has also been used on the back of an outboard motor support shaft. Such trolling plates are disclosed in U.S. Pat. No. 2,155,112 to Anderson and U.S. Pat. No. 2,548,121 to Reid. These types of trolling plates create undesirable stresses on the motor housing and the motor mounts and occasionally result in breakage of the trolling plate mounting bracket. In addition, these plates produce undesirable torques which adversely affect the steering capabilities of the boat. Further, the plates occasionally result in the tangling of downrigger wires in the propeller wash and are not adaptable for inboard motors.